Рисование треугольника Серпинского с помощью GTK

#include <iostream>
#include "gwindow.h"
#include "math.h"
#include "simpio.h"
using namespace std;
 
/* Function prototypes */
 
void drawTriangle(GWindow & gw, GPoint pt, int order, double length);
 
/*
 * Main program that asks the user for an edge length and a fractal order and draws the resulting
 * Sierpinski Triangle in the center of the graphics window.
 */
 
int main() {
   GWindow gw(600, 500);
   int length = getInteger("Enter edge length: ");
   int order = getInteger("Enter fractal order: ");
   double originalX = (gw.getWidth() - length)/2;
   double originalY = gw.getHeight()/2 + (length/2 * sqrt(3))/2;
   GPoint originalPoint(originalX, originalY);
   drawTriangle(gw, originalPoint, order, length);
   return 0;
}
 
/*
 * Draws a Sierpinski triangle of a given order recursively.
 */
void drawTriangle(GWindow & gw, GPoint pt, int order, double length) {
    if (order == 0) { //Draws simple triangle
        pt = gw.drawPolarLine(pt, length, 0);
        pt = gw.drawPolarLine(pt, length, 120);
        pt = gw.drawPolarLine(pt, length, -120);
    }
    else {
        GPoint newPoint1(pt.getX(), pt.getY()); //New points for each new Sierpinski triangles (bottom left triangle)
        GPoint newPoint2(pt.getX() + length/4, pt.getY() - ((length*sqrt(3)/4))); //(top triangle)
        GPoint newPoint3(pt.getX() + length/2, pt.getY()); //(bottom right triangle)
        drawTriangle(gw, newPoint1, order - 1, length/2); //Draws three Sierpinski triangles of one order less
        drawTriangle(gw, newPoint2, order - 1, length/2); //than the previous in the corners of the previous triangle
        drawTriangle(gw, newPoint3, order - 1, length/2); //with half the edge length
    }
}

int main() {
    using std::something;
    something();
}

else {
        GPoint newPoint1(pt.getX(), pt.getY()); //New points for each new Sierpinski triangles (bottom left triangle)
        GPoint newPoint2(pt.getX() + length/4, pt.getY() - ((length*sqrt(3)/4))); //(top triangle)
        GPoint newPoint3(pt.getX() + length/2, pt.getY()); //(bottom right triangle)
        drawTriangle(gw, newPoint1, order, length/2); //Draws three Sierpinski triangles of one order less
        drawTriangle(gw, newPoint2, order, length/2); //than the previous in the corners of the previous triangle
        drawTriangle(gw, newPoint3, order, length/2); //with half the edge length
        --order;
    }

int f1(int  order) {return  order ?    order    *f1(order-1) : 1;}
int f2(int *order) {return *order ? ((*order)--)*f2(order)   : 1;}
 
int main() {int order=7; std::cout<<f1(order)<<'\n'; std::cout<<f2(&order)<<'\n';}